Underreamer.



W. M. KECK.

UNDERRBAMER.

APPLICATION FILED SEPT,13.1011.

1,040,848. Patented Oct. 8, 1912.

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5] n uemioz Kcflw l W bwmeo y W. M. KECK. UNDERREAMBR.

APPLICATION FILED SEPT.13,1911. 1,040,348, Patented 00B. 8, 1012.

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VJILLIA'M M. KECK, 0 CGALINGA, CALIFORNIA.

' UNDERREAMEB.

Specification of Letters Patent.

Patented Oct 8, 1912.

implication filed September 13, 1.911. Serial No. 649,074.

To all whom it may concern:

Be it known thatl, lViimiAii M. linen, a

citizen of the United States, residing at Coaliiiga, in the county ot' Fresno and State of California, have in ienletl new and useful Improvements in Underi'eiilncrs, of which the following is a SPQClllmtlUIlU This invention relates to reaniers and more particularly to uiulerreaincrs used in connection with the sinking of oil Well tubes and the like.

One of the principal objects of. the invention is the provisioii of a device of this charactor in which the cutters are automatically expanded when the mandrel is projected from the casing and which are automatically collapsed when the mandrel is drawn into the casing.

Further objects of the invention will appear as thefollowing specific description is read in connection with the accompanying drawings, which form a part of this application, and in which Figure .l is a side elevation of the device shown projected from the well casing. Fig. 2 is a longitudinal sectional view with the casing also in section. Fig. 3 is an cnd elevation. Fig. 41- is a sectional view taken at right angles to 2 on the line l--4l of said figure. Fig. 5 is a perspective view of the expanding rod removed from the casing.

Fi 6 is a similar view of one of the cutter members looking from the inside.

Referring more particularly to the drawings, 1 represents the mandrel WhlCll is substantially cylindrical for a portion of its length and than tapers toward the upper end where it is provided with a tapered threaded extension 2 adapted :l'or connection with the auger stem or sinker. The mandrel is provided with a centralhore 3 which is reduced at 4 to provide a shoulder 5 and the latter portion communicates with a transverse slot. 6, the Walls of which are IlZCto ed, as shown at 'i, the side walls at each r being inciiii d inw rrdly, as shown 1 i Seated within the and pivotally mounted upon pins 9 are tin, cutter members iliwhich are provided with narrowed Webs l projectingthrough the slot 6 on either side thereof and provided with a cam outer surface 12, for a purpose to be hereinafter described The arrowed webs 12 form shoulders 13 on iei side thereof which are adapted to eng i e the ii'iclined walls 8 so as to limit the out ard, movement oi? the cutwith a groove 14 to engage the ribs 15 extending longitudinally of the tapered expanding head 16 which is formed at the end of the expanding rod 17. The rod 17 is squared, as shown at 18, and this squared portion travels in the reduced portion 4 of the channel 3 and is of a width equal to the width of the ribs 15.

Passing through the squared portion 18 are suitable wcdging keys 19 and 20 which have their ends pro ecting through slots 21 in the side of the mandrel and engaged loosely with plates 22 which are double dove tailed in the channels 23. 'lhesc channels gradually increase in depth from nothing to the forward end of the mandrel and so act upon the plates 9:2, when they are moved forward, as to cause them to disappear or move out of the path of the casing. The plates are slightly tapei edon their upper ends, as shown at 2i.

The rod 17 has an adjustable collar 25 mounted thereon and, surrounding the rod between the collar and the shoulder 5, is a spiral spring so whichnormally acts to draw the head ll between the cutting members 10 so that, immediately upoii'the projection of the mandrel beyond the end of the casing, the cutters will be expanded into operative working position. \Vhen the mandrel is drawn into the casing the plates 22 will be engaged by the casing: and forced downwardly until they disappear or are carried out of the path of the casing by the action of the channels 23. At this time the cam surfaces of the cutter members will engage (licensing and force the cutter members inwardly. As long as the iuandrel is held in the casing the head ll) will be preventedfrom moving by the action ol'the spring 26, Having thus described the invention, what lclaun as new 1s:-

, l. A reamer comprising a mandrel, cutiois pivoted thereto, a tapered expanding head arranged between the cutters, a spring for normally drawing the head into the mandrel for throwing the cutters to expanded position a member carried by the head and projecting through opposite sides of the mandrel, and plates slid 1y mounted thereon and adapted to be engaged by a well casing, said mandrel provided with means to throw the plates out of engagement with the casing.

2. In a device of the class described, a man- I tors. Each one of the cutters is provided adapted to plates slidably mounted in said channels,

drel having grooves on its sides which grad-d 'nally increase in depth toward the forward end of the mandrel, cutters pivoted to the mandrel, a spring operated expending head normally expand the cutters,

and means carried by the head and loosely engaged with the plates and connecting these parts.

3. A. reamer comprising a niandrel having channels fqhmed in its sldes With undercut walls, saidchannels gradually increasingin depth from nothing to the outer end' of the mandrel, plates shdably mounted in said "in lo es chaimels and having a depth lessthan the greatest depth of the channel, cutters pivoted tothe mandrel, an expanding member normally actuated to expand the cutters, and

-a connection between the expanded member and the plates which is rigid with the expending member and loose upon the'plates.

In testimony whereof I affix my signature in presence of two Witnesses.

WILLIAM M. anon, Witnesses STANLEY Penman,- A. E KINNEY. 

